 <script>
import useStore from '../../store/index.js';
const {app} = useStore()
   export default {
     data() {
       return {
         wh:0,
         cateList: [],
         active:0,
         catelevel2:[],
         scrollTop:0
       };
     },
     onLoad() {
       const sysInfo = uni.getSystemInfoSync()
       this.wh = sysInfo.windowHeight - 50
       this.getCateList()
     },
    onShow() {
     app.setTabBar()
    },
     methods:{
       async getCateList() {
           // 发起请求
           const { data: res } = await uni.$http.get('/categories')
           // 判断是否获取失败
           if (res.meta.status !== 200) return uni.$showMsg()
           // 转存数据
           this.cateList = res.message
           this.catelevel2 = res.message[0].children
         },
         activeChanged(i) {
           this.active = i
           this.catelevel2 =  this.cateList[i].children
          this.scrollTop = this.scrollTop === 0 ? 1 : 0
          },
          gotoGoodsList(item3){
            uni.navigateTo({
              url:'/subpkg/goods_list/goods_list?cid=' + item3.cat_id
            })
          },
          gotoSearch(){
            uni.navigateTo({
              url:'/subpkg/search/search'
            })
          }
     }
   }
 </script>
 <template>
   <my-search @click="gotoSearch()"></my-search>
   <view class="scroll-view-container">
     <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
       <block v-for="(item, i) in cateList" :key="i">
         <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
       </block>
     </scroll-view>
     <scroll-view scroll-y class="right-scroll-view" :style="{height:wh + 'px'}" :scroll-top="{scrollTop}">
      <view class="cate-lv2" v-for="(item,i2) in catelevel2" :key="i2">
        <view class="cate-lv2-title">/ {{item.cat_name}} /</view>
        <view class="cate-lv3-list">
              <!-- 三级分类 Item 项 -->
              <view class="cate-lv3-item" v-for="(item3, i3) in item.children" :key="i3" @click="gotoGoodsList(item3)">
                <!-- 图片 -->
                <image :src="item3.cat_icon"></image>
                <!-- 文本 -->
                <text>{{item3.cat_name}}</text>
              </view>
            </view>
      </view>
     </scroll-view>
   </view>
 </template>

 <style lang="scss">
.scroll-view-container {
  display: flex;
  
  .left-scroll-view {
    width: 120px;
    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;

      // 激活项的样式
      &.active {
        background-color: #ffffff;
        position: relative;

        // 渲染激活项左侧的红色指示边线
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left: 0;
          top: 50%;
          transform: translateY(-50%);
        }
      }
    }
    }
    
  .right-scroll-view{
    .cate-lv2-title{
      font-size: 12px;
        font-weight: bold;
        text-align: center;
        padding: 15px 0;
    }
    .cate-lv3-list {
      display: flex;
      flex-wrap: wrap;
    
      .cate-lv3-item {
        width: 33.33%;
        margin-bottom: 10px;
        display: flex;
        flex-direction: column;
        align-items: center;
    
        image {
          width: 60px;
          height: 60px;
        }
    
        text {
          font-size: 12px;
        }
      }
    }
  }
    
}
</style>
